Driving mechanism for walking beam conveyers



Dec. 25, 1951 MARvlN Er AL 2,580,114

DRIVING MECHANISM FOR WALKING BEAM CONVEYERS Filed Aug. 28, 1948 3Sheets-Shet l A TTORNEYS Dec. 25, 1951 s, MARVIN ETAL 2,580,114

DRIVING MECHANISM FOR WALKING BEAM CONVEYERS File d Aug. 28, 1948 sSheets-Sheet 2 A rromvErs Dec 25, 1951 5 MARVlN ETAL 2,580,114

DRIVING MECHANISM FOR WALKING BEAM CONVEYERS Filed Aug. 28, 1948 v 3Sheets-Sheet 3 INVENTOR W/LL/AM H, ORTH 5 STA/V BY LE) MARVIN A TTORNEYS the rocker arms are vertical, as shown in the right hand portionof Figure 3, the rails 80 carried by the movable frame are raised toproject above the fixed rails 22, while the upper edges of the rails 88are lowered beneath the upper edges of the fixed rails 22 when therocker arms are substantially inclined from the vertical, as shown inthe left hand portion of Figure 3, the amplitude of the rocker armsbeing limited by the throw of the pitman arms 40 and eccentrics 34.

The movable frame is prevented from endwise displacement from the wheels48 and I2, and is also adapted for reciprocal movement by the followingmechanism: The middle pair of shoes 82 is provided with outwardlyextending rollers 86 extending between spaced ribs 88 on the inner sideof the upper end of rocker arms 90 pivotally carried on the outer endsof rocker shaft 68. The rocker arms 90 are provided with longitudinalslots 92 in which flanged pivot studs 94 are selectively positionable inaccordance with suitable indicia on scales 96 adjacent the slots, saidstuds being adapted to be secured to the end of pitman arms 98 by nutsI00. The nuts I secure the studs 94 andthe ends of the pitman arms 98 tothe rocker arms 90 in any desired position in the slots 92. The oppositeends of the pitman arms 98 are secured as by pins I02 to hearing strapsI04 comprising yokes I06 and I08 having their ends secured together andin engagement with the eccentrics 32 between the flanges 34 thereof.

The eccentrics 32 and 3B are preferably, though not necessarily, of thesame size and are so arranged with respect to each other that upon therotation of shaft 28 in a clockwise direction, as viewed in Figures 1and 3, caused by suitable driving means, not shown, in engagement with achain drive I I0 passing over the gear 30 on shaft 28, the rocker arms54 and 62 move from the inclined position shown at the left side ofFigure 3 to the vertical position shown at the right side of Figure 3,and back to the inclined position, during one complete revolution of theshaft '28. Meanwhile, the rocker arms 90 move from a position whereinthey are inclined to the left of a vertical position to a positionwherein they are inclined to the right of the vertical, and back again,during one complete revolution of the shaft 28. The resultant movementimparted to the rails 80 causes them to travel more upwardly thanforwardly in the first stage of the cycle, until the rails 80 rise abovethe rails 22, this being due to a certain degree of lost motion betweenthe rollers 86 of the shoes 82 and the ribs 88 of the rocker arms 90when the direction of movement of the latter is reversed; upwardly to amaximum degree and forwardly to a maximum degree: more downwardly thanrearwardly until the rails 80 dip below the rails 22, also due to thelost motion between the rollers 86 and the ribs 88 when the rocker armsreverse their direction; and downwardly to a maximum degree andrearwardly to a maximum degree to complete the full cycle. During thecycle of travel, the driving connection between the rollers 80 and ribs88 does not hinder the vertical movement of the rails 80, and thevertical movement of the rollers 86 is not sufiicient to bring saidrollers out of engagement with the ribs 88.

The amplitude of reciprocatory movement of the movable frame may bevaried by changing the points of connection between the ends of thepitman arms 98 and the rocker arms within the slots 92. Thus, if thearms 98 are connected to the rocker arms at the lower end of the slots,the amplitude of the movable frame will be at a maximum, while if theconnection is made at the upper ends of the slots the amplitude will beat a minimum.

It will be seen from the foregoing description of the driving mechanismof the invention and the operation thereof that we have provided anovel, simple and efficient arrangement for the imparting of motion tothe movable frame portion of a walking beam type conveyor. v

While the preferred embodiment of the invention has been shown anddescribed, it will be understood that the embodiment set forth issusceptible of change within the spirit of the invention and the scopeof the appended claim.

What we claim as new and desire to secure by Letters Patent is:

In combination, a fixed frame having a plurality of parallel spacedsupporting elements, a movable frame having a plurality of parallelspaced supporting elements, and driving means for imparting a compoundmotion to said movable frame to cause the supporting elements thereof totravel a cyclic path above and forwardly and below and rearwardly of thesupporting elements of the fixed frame; said driving means comprising aplurality of pairs of pivotally mounted arms, links interconnecting saidpairs of arms to maintain them in parallelism, rollers carried by saidarms adjacent the upper ends thereof for the support of said movableframe, a driven shaft, a first pair of eccentrics mounted on said shaftfor rotation therewith, pitman arms mounted on the peripheries of saideccentrics and each connected to one of said links adapted to rock saidpivotally mounted arms from an inclined position to a substantiallyvertical position and back to said inclined position upon a completerotation of said shaft, another pair of pivotally mounted arms, anotherpair of eccentrics mounted on said shaft for rotation therewith, otherpitman arms mounted on the peripheries of said eccentrics, slots in saidother pair of arms for connecting said other pair of pitman arms theretoat various distances from the pivotal axis of said arms, and a slidablelost motion connection between said slotted arms and said movable frameadapted to impart a horizontal component of motion to said frame uponthe rocking motion of said slotted arms.

STANLEY MARVIN. WILLIAM H. ORTH.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Holm Dec. 31, 1935

